1//===----------------------------------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9// <ostream>
10
11// template <class charT, class traits = char_traits<charT> >
12// class basic_ostream::sentry;
13
14// ~sentry();
15
16#include <ostream>
17#include <cassert>
18
19#include "test_macros.h"
20
21int sync_called = 0;
22
23template <class CharT>
24struct testbuf1
25 : public std::basic_streambuf<CharT>
26{
27 testbuf1() {}
28
29protected:
30
31 int virtual sync()
32 {
33 ++sync_called;
34 return 1;
35 }
36};
37
38int main(int, char**)
39{
40 {
41 std::ostream os((std::streambuf*)0);
42 std::ostream::sentry s(os);
43 assert(!bool(s));
44 }
45 assert(sync_called == 0);
46 {
47 testbuf1<char> sb;
48 std::ostream os(&sb);
49 std::ostream::sentry s(os);
50 assert(bool(s));
51 }
52 assert(sync_called == 0);
53 {
54 testbuf1<char> sb;
55 std::ostream os(&sb);
56 std::ostream::sentry s(os);
57 assert(bool(s));
58 std::unitbuf(base&: os);
59 }
60 assert(sync_called == 1);
61#ifndef TEST_HAS_NO_EXCEPTIONS
62 {
63 testbuf1<char> sb;
64 std::ostream os(&sb);
65 try
66 {
67 std::ostream::sentry s(os);
68 assert(bool(s));
69 std::unitbuf(base&: os);
70 throw 1;
71 }
72 catch (...)
73 {
74 }
75 assert(sync_called == 1);
76 }
77#endif
78
79 return 0;
80}
81

source code of libcxx/test/std/input.output/iostream.format/output.streams/ostream_sentry/destruct.pass.cpp